Current-carrying plug



H. A. DOUGLAS. CURRENT CARRYING PLUG.

MPHCATIONl FILED OCT. I4, 1918.

1,347,738. PatentedJuly 27,1920.

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UNITED lSTATES PATENT OFFICE.

HARRY A. noU'GLAs, or BaoNsoN, MICHIGAN.

' CURRENT-emitirse' PLUG.

Original application-med February 4,

terminal conductor or conductors passedv into the plug either from end to.end of the plug or through `a sideof` the 'plug and thence toward ,one end of the plug. This feature of my invention may bep'ractised Y in conjunction with a so-called double pole plug, or a vsingle pole plug.

In carrying out this feature of the invention I provide a plug with one bore, if the plug is a single pole plug or two bores if the plug is a double pole plug, such bore or bores extending longitudinally through the plug. There is also provided one or two bores, as the case may be, which communicate with the aforesaid bore or bores and extend laterally into the plug. The longitudinally disposed boreor bores are thus alwayjs in service in' whole or in part whether the conductor or conductors are passed into the plu longitudinally or laterally thereof, the ateral bores not being used, as the invention is preferably practised, when the conductors extend from'end to end of the plug.

In accordance with another feature of the invention the plug is divided lengthwise into sections, a half of each bore, or the bore if there is but one, bein formed in each section of the plug. Wiere the plug. is formedin sections it is desirably-provided withVV a sheath for maintaining. the sections 1n assembly. v

plug is usually to be coupled with a socket. VThe plug of my invention has been used as -an element distinct from the plug rtion or base-of an incandescent lamp to include such lamp in circuit but I do not wish so to limit the plug of my invention.

I Vwill explain my invention more fully by reference to the accompanying drawing showing' the preferred embodiment thereof and in which Figure 1 is a view, in longitudinal section, illustrating a connector having a shell and plug equipped in accordance u Specication of Letters atent.

' gures.

Patented July 27,1920.

lin elevation within the shell; Fig. 2 is a View on line 2-2 of Fig. 1; Fig. 3 shows another disposition of conductorsI within the plug of the connector; Fig. 4 is' a view in elevationfof the structure as it appears in Fig. 3; Fig. 5 is a view in plan of the rear partof the shell appearing in-Fig. 4; Fig. 5a4 isa. view of the shell as it ap ears in Fig. 5 minus the retaining spring; ig. 6 is a view in perspective showing the two parts of the core of the plug in separated relation; and Fig. 7 shows in perspective the sheath that I prefer to employ for the plug when it is used as illustrated in Fig. 1.

1918, SerialNo. 215,330. Divided and this application led October 14, 191s. serial No. 258,065.

.Like parts are indicated by similar characters of reference' throughout the different The shell 1 of the connector is preferably metallic. Its `front end is provided with bayonet slots 2 adapted to receive the bayo- -net pins 3 that project laterally from the base or plug portion 4E of the incandescent lampv 5. The iilament 6 of the lamp is connected with the contacts 7 and 8 that are provided u on the base or plug portion of the lamp. oth of these contacts are shown as being upon the inner end face of the lamp base inasmuch as the connector illus- -trated is a so-called two pole connector, but

to which type of connector the invention is not to be limited. A contact carrier 9, of insulating material, is ixedlv located in the mid portion of the shell. etallic spring barrels 10 and 11 are secured' to and pass through the contact carrier 9. Coiled springs 12 and 13 are located within the spring barrels. These coiled s rings press the contact plungers 14 and 15 orwardly to have them respectively engage the contacts 7 and 8 upon the lamp base. These same springs press the contact plungers 16 and 1 rearwardly to engage them with contacts 18 and 19 that are suitably connected with the terminals of a source Aof 'current through the intermediationof flexible con-v ductors 20 and 21.

The contacts 18 and 19, the conductors 20 and 21 leading to these contacts, and the coverings or servingffor these conductors are disposed within and are carried by a contact carrying plug of insulating material, which contact carrying plug is preferably divided longitudinally into sections by being symmetrically formed into halves 22-23'as illustrated in Fig. 6. Two cylindrical bores 24,25 extend longitudinally through the contact carrying plug 22-23, a' half of each bore being formed in each half` of said contact carrying plug. Transversely extended bores'26, 27 merge with the bores 24, 25, the

inner ends'of the bores 26, 27 being curved -forwardly `to be tangential `to and thereb merge gradually with the other bores.

half of each of the bores 26, 27 is formed in' each half of the contact carrying plug 22- 23. When the conductors 20, 21 extend into the plug 22-'-23 laterally of such plug the sheath 28, clearly illustrated in Fig. 7 is employed, the bore of this sheath being equal in diameter to the diameter of the plug whereby the two halves ofthe plug are prevented from slipping transversely of the sheath. The rear ends of the plug halves 22,23 abut against the rear end wall 29 of the sheath 28. The forward end of the sheath is turned 'inwardlyas indicated at 30 in Fig. 1, to engage the front ends of the plug halves 22, 23. The two halves of the plug are thus prevented from slipping endwise withrespect to each other. A ferrule 31 incloses the conductors 2O and 21 and -a ltube 32 through Which-these conductors are led. This ferrule'has a head or flange 33 24, 25. In the arrangement illustrated in (Figs. 3 and 4, the conductors project through the rear end of the contactcarrying plug 22-23 extending throughout the entire length of. the bores 24, 25 and passing through no part of the bores v26, 27. In this arrangement the ferrule 31 is omitted and the sheath 28 is minus the longitudinal slot v -als 34 but has its rear end open as indicated at 35 in order that the conductors may pass from the plug. To maintain the conductors 20, 21 and their-terminal contacts 18 and 19 in assembly with the contact carrying plug 22-23, I provide said contacts with flanges 35, 36l that are received within Athe annular enlargements 37, 38 of the vbores 24,

v25. The sheath of the plug 22-23, whether of the form illustrated in Fig. 1l or of the form illustrated in Fig. 3, is provided with bayonet pin extensions or projections 39 receivable within bayonet slots or channels 40 provided in the rear end of the shelll. Instead of relying upon-the contacts 16 and 17 to maintain the bayonet pins 39 in their.

seats within the bayonet slots 40 I provide a strip or Wire retaining sprin 41 extending laterally of the shell and dlsposed in the zone of the bayonet slots 40 and which retaining spring has an arrangement that is well illustrated in Figs. 2, 3 and 5, this feature being claimed in lmy original application Serial No. 215,330, filed February 4, 1918, of which the present application is a division. This spring is depressed at its intermediate portion 41 to contact withy the sheath 28 or 28 of the plug, this depressed portion being received in the transverse slot or opening 42 and being substantially coextensive with this slot to have abutting engagement at the ends of the slot where the spring rises to have its sections 412 engage the exterior of the shell 1. The ends of the retaining spring are 'depressed to enter the bayonet slots 40 and engage the sheath 28 or 28, these spring ends extending across the entrance branches of the bayonet slots 40 to be `engaged by the bayonet pins 39. When the plug 22-23 isA inserted the bayonet pins 39 engage the spring 41 and flex it longitudinally of the shell from its normal plane, this plane being resumed by the spring when the bayonet pins are in their seats owing to the resilience of the spring and the substantially fixed anchorage lof the spring at its mid portion to the shell, theends of the spring 41 serving to hold these bayonet pins in their seats. Any preferred means may be employed for holding the spring 41 in assembly with the shell 1. In the preferred embodiment of the invention two ears 43 are struck up from the shell where the mid portion 41 of the spring is received and are lapped over .this intermediate portion of the spring to hold the spring in the assembly illustrated clearly in Fig. 2. These ears 43 serve to cooperate with the contiguous portions of the shell and also with the underlying sheath normally to hold the spring in its plane, the engagement of the spring and shell being sufliciently irm'to establish a substantiallyxed' relation between the mid section 41 of the spring with the shell so that the spring is merely permitted to yield, due to its own resilience, when the plug 22-23 is being inserted within or removed from 'the shell. The ends of the spring are depressed into the bayonet slots to. engage the sheath of the plug and thereby have full effective engagement with the bayonet pins. While the spring 41 is shown for the purpose of holding the plug in'assembly with the shell it is obvious that it is not limited to the nature of the contact4 carrier' that it servesto hold in position.

While I have herein shown and 'particularly described the preferred embodiment of -my invention I do not wish to belimited to the precise details of construction shown as changes may lreadily be made without departing from the spirit of my invention, but with a longitudinal vslot through' which the 1o having thus described my invention I claim conductor is passed, and a ferrule surroundas new and desire to secure by Letters Pating said conductor and projecting into the ent the following sheath through said slot and having a A current carrying plug having a Dore` flange within the interior of the sheath to extending thereinto laterally and toward prevent lateral Withdrawal of the ferrule. 15 one end of the plug, in combination with a In Witness whereof, I hereunto subscribe conductor extending into the plug through my name this 24th day of Sept. A. D., 1918. said bore, a sheath for the plug provided HARRY A. DOUGLAS. 

